Dastin et al U.S. Pat. No. 5,200,791 is illustrative in that it is directed to achieving improved registration in a multicolor imaging system. It differs basically from this invention in that during each imaging operation it employs a sensor to sense the position of the photoconductor. At column 7, beginning at line 4 it instructs away from a mechanical synchronization of the photoconductor drum and the accumulator drum.
Egawa U.S. Pat. No. 5,264,870 is illustrative since it employs a reference signal from its accumulator roller 13. Takada et al U.S. Pat. No. 4,723,145 is illustrative in that it has separate drives to its optical system and its accumulator, but does not periodically drive them from the same signal.
This invention involves the driving of the accumulator member during operation under control signals which are uniquely determined for each machine, which may be at final completion of the machine or from a control panel setting. No sensing of the position of the photosensitive member or the accumulator member is involved during operating. The timing of the operation of the optical system is sensed and employed to periodically control the drive of the accumulator member. The system of this invention can be described as a frequency locked loop with periodic phase correction to maintain a virtual phase locked system.